Some men who take the drug finasteride (Propecia) to slow a receding hair line may also find it reduces their interest in drinking alcohol, new research reveals.

Almost two-thirds of the men in the study noticed they were drinking less alcohol than before taking Propecia, said study researcher Dr. Michael Irwig, an endocrinologist and assistant professor of medicine at George Washington University School of Medicine.

But the decrease in drinking seen in the study may not be found in all men who use the popular hair-loss treatment. (A higher dose of finasteride is also prescribed to men for an enlarged prostate, and is sold as Proscar.)

The study, which was aimed at better understanding the drug's sexual side effects, looked at only younger men, ages 46 and under, who had quit taking the medication for male-pattern hair loss for at least three months, yet continued to experience effects such as a reduced sex drive and erectile dysfunction.

Although the exact mechanism for reduced alcohol consumption is not known, Irwig said he suspects that Propecia interferes with the brain's ability to make certain hormones, known as neurosteroids, which are likely linked to drinking alcohol.

The findings are the first to link finasteride use in men with changes in alcohol consumption, an effect previously shown in male mice, the researchers said in their study, published online June 13 in the journal Alcoholism: Clinical & Experimental Research.